Modified methods for direct assay of levonorgestrel and prolactin levels during two monthly injections

ABSTRACT

Modified radioimmunoassay [RIA] and chemiluminescence [CL] methods were adapted for ultra-micro determination of levonorgestrel [L- Nog] and prolactin [PRL] in biological fluids. No prior extraction was needed. The methods yielded precise results with coefficient of variation of < 10%. The methods correlated well with USP XXIII and the conventional RIA methods. The correlation coefficients [r] were 0.92, 0.94 for L-Nog and 0.91 for PRL. The sensitivity of modified RIA for L-Nog was 100 Pmol/L. Modified CL method for PRL showed excellent sensitivity [0.04 ng/ml]. Modified methods were applied to quantitate L-Nog and PRL serum levels during two monthly L-Nog injection. The modified analytical techniques provided accurate, precise, time saving and sensitive methods for analysis of L-Nog and PRL serum levels